Socket for incandescent lamps



(No Model.) I

- A. EKSTROM.

SOCKET FOR INGANDESGENT LAMPS.

No. 501,205. Patented Julyll, 1893.

FIEA- I llrrrrs STAT S i PATENT FFICE.

AXEL EKSTRCM, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THE THOMSON- HOUSTON ELECTRIC COMPANY, OF CONNECTICUT.

SOCKET FOR'INCANDESCENT LAMPS.

SPECIFICATION forming part of Letters Patent No. 501,205, dated July 1 1, 18953.

Application filed une 27,1892.

T0 aZZ whom it may concern.-

Be it known that I, AXEL EKsTRoM, a citizen of the United States, residing at Lynn, county of Essex, State of Massachusetts, have invented a certain new and useful Improvement in Sockets for Incandescent Lamps, of which the following is a specification.

The invention is an improvement in sockets for incandescent lamps, and is particularly applicable to incandescent lamps intended for use out of doors, such as street lamps in a municipal system, or any incandescent lamp which is used or located in places where it is exposed to rain or moisture, as in mines, tunnels, and certain mills.

One of the chief objects of the invention is to avoid the use of the screws which are usually employed to secure the base to the shell. These screws are very apt to be dropped and lost in working about the socket, and the screw holes leave openings through which water can enter the socket and injure the insulation, provoking short-circuits, and causing corrosion of the metal. The invention avoids all of these difficulties by-avoiding the necessity of using screws. Moreover there is obtained a very simple mechanical structure which is easily wired up.

In the drawings Figure 1 is a perspective view of the base. Fig. 2 is a similar view of the contact carrying piece. Fig. 3 is a similar view of the inclosing shell, and Fig. 4 is a central longitudinal section of the base and part of the shell.

The socket consists of three parts, a base .3, a contact carrying piece A and a shell C. The base B has a central threaded opening by which it can be screwed to an iron or other pipe through which the lead wires are carried. It is provided with a flange B having a screw thread at S which can be engaged by the threads S of the shell 0. The base B has a raised portion D on its inner side, non-circular in shape so as to prevent the contact carrying piece from rotating, as hereinafteredescribed. The contact carrying piece A consists of a supporting piece X on the lamp side of which are lamp terminals 0, O, the former being the ordinary screw terminal to which the lamp is attached,and the latter a bent spring forming a rubbing terminal. Above Serial No. 188,098- (No model.)

the support X and attached thereto by brackets P is a separate piece F recessed at D to match the raised portion Don the base and of such size that the edge of the shell C bears against it as seen in Fig. 4 clamping the contact carrying piece in place when the parts are together. Between the pieces F and X is left an open place where are situated the line contacts as indicated at T. The shell C has a screw thread E at its upper end which takes into the thread S on the base, and as already described holds the different parts in place. As the contact carrying piece is kept from rotation the lamp may be screwed tightly to the socket without difficulty. It is evident that the screw-threads on the base and shell may be mutilated or segmentary; or that a bayonet joint maybe used. Moreover, the piece A may be struck up with a recess instead of a hole to fit over the projection D.

What I claim as new, and desire to secure by Letters Patent, is-

1. An incandescent lamp socket having a flanged base, provided with a central non-circular raised portion or projection D, a contact carrying piece having a part F recessed so as to fit over the said projection, and a shell adapted to be screwed to the base thereby clamping the parts together, as described.

2. An incandescent lamp socket comprising a base, having acentral non-circular projection, a contact carrying piece having a sup port X with lamp terminals on one side, and a raised piece F held above and away from the support X and engaging with the projection upon the base to prevent rotation when the parts are'in place, and a shell inclosing the contact carrying piece clamping the parts together by its attachment to the base, as described.

3. .An incandescent lamp socket, comprisfitting over said projection and so held against rotation and having a flange clamped between the base and the end of the shell, substantially as described.

5. A lamp socket comprisinga base having a central non-circular projection, a separate contact carrying piece having screw and rub bing lamp terminal contacts, and matching 1 the projection upon the base so as to be held 

